was still moving the fbi says ciancia returned, killing him, and wounded two more officers and a teacher. >> he saw the gunman. he felt his leg go, turn into jelly. >> police shot ciancia four times, discovering a hand written note describing how he wanted to instill fear on your traitorus minds. which is detailed further on cnn >> he said if i just kill one, my mission is accomplished >> paul is their son, and brother. we'll continue to love and care for him. >> reporter: detectives combed through his southern california apartment and other residences, trying to determine what set him off. classmates describe him as a loner. a former roommate says he was a nice guy. >> going back to jersey, working for his dad, making amends can family problems >> now, the attorney general says they may have to rethink airport procedures >> it's something we need toechl yammin given what happened in los angeles. >> reporter: investigators found five magazines of ammunition at the crime scene the alleged gunman is now unresponsive in the hospital. if regaining consciousness, co face the death penalty.